


Infernal Ingredients

by psychomachia



Category: Fate/Zero
Genre: Alternate Universe - Modern Setting, M/M
Language: English
Status: Completed
Published: 2018-02-07
Updated: 2018-02-13
Packaged: 2019-03-15 00:47:56
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 4,580
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13602000
Author URL: https://archiveofourown.org/users/psychomachia/pseuds/psychomachia
Summary: “Isn't it time for your lunch?” Maiya asks. “Perhaps you'll get lucky and his father will come back from the dead and sell you a burger.”





	1. Chapter 1

**Author's Note:**

  * For [Reishiin](https://archiveofourown.org/users/Reishiin/gifts).

**Summary for the Chapter:**

> Kiritsugu refuses to believe he's in a romantic comedy. He's only halfway correct.

### Day One

Kiritsugu's day follows the same routine. He wakes up, makes coffee and checks his newspaper. Then he takes the train to work, greets his fellow officers, and proceeds to have a thoroughly uneventful day taking reports of lost pets, stolen purses, and occasional missing children. It is a simple routine, the highlight of which is the burger he gets at the little stand near his kōban. Kotomine's burgers are nothing spectacular, but they are filling, cheap, and the old man just nods when he orders without making conversation.

It's perfect.

And like every good thing in his life, inevitably ruined on a brisk autumn afternoon when he walks to the stand and is met not with the pleasant countenance of an old man, but an intent stare from a younger one in a dark blue jacket who refuses to break eye contact.

This, of course, means Kiritsugu will have to violate one of his long-cherished traditions and actually talk to the man. He hates him already. “Where's the owner?”

“My father's not here,” he says, still staring. “I'm his son, Kotomine Kirei.”

“Well, I'm a regular,” he says, “and I'd like to order--”

“One bowl of mapo tofu.”

“Excuse me?” Kiritsugu asks.

“You'd like to order that.”

“No!” he snaps. “I used to--”

“That's all I sell,” Kotomine says. He leans forward and Kiritsugu longs for the days of personal space.”So that's what you're getting.” His eyes gleam and is that a smirk on his face?

Kiritsugu storms away.

“You'll be back,” he hears behind him.

Back at the kōban, having stubbornly resolved to eat nothing, he says, “Just who the hell is Kotomine Kirei?”

 

### Day Two

“He's Mr. Kotomine's son,” Maiya says as she finishes her report and looks up at him. “His father retired and left the stand to him.'

“When did he retire?” Kiritsugu asks. “Why didn't I know about this?”

“Did you ever actually talk to him?”

She has a fair point, so Kiritsugu redirects. “That's probably a cover story for him murdering him. I don't trust him.”

“You don't trust anyone.”

“But I really don't trust him.”

“Isn't it time for your lunch?” Maiya asks. “Perhaps you'll get lucky and his father will come back from the dead and sell you a burger.”

Luck is not something Kiritsugu possesses, so he is not surprised to see that same annoying figure at the stand, surrounded by people. It seems he's popular, so it's a bit of a shock when he sees people leaving empty-handed, faces downcast.

“I guess your cooking's an acquired taste,” he says as he walks up to Kotomine. “Maybe if you'd change your menu, you might actually get people ordering food from you.”

“Oh, they tried to order,” Kotomine says with that same annoying smirk. “I just didn't let them.”

“So if I tried to order--”

“One bowl of mapo tofu coming up.”

“But I don't actually want to eat your food.”

“Which is why you can.”

Kiritsugu has sworn not to make a habit of dramatic exits, but he feels this line warrants it so he does.

“You'll be back.”

When he returns, empty-handed, Maiya just lifts her eyebrows and says, “So, you're eating from the vending machine again?”

He refuses to dignify this with an answer.

 

### Day Three

Kiritsugu knows he is a brilliant detective, capable of amazing feats of deduction. The only reason he isn't out solving murders is because he chooses to use his skills to help his community. That, and a certain pompous windbag who refuses to let go of his grudges about certain hotels that honestly were one electrical short circuit away from a fire anyhow.

He's perversely glad the man's wife left him (and refuses to think about his own separation).

So he knows there's something up with Kotomine that isn't quite right.

“Well, obviously,” Maiya says, “because he keeps talking to you. I mean, you're my best friend and partner and I'd utterly destroy anyone who hurt you, but you're not really good with people.”

“I'm still going to make some calls,” he says, ignoring the terrifying, murderous elephant in the room.

> Facts Kiritsugu has learned by the end of the day
> 
>   1. Kotomine Kirei does have a father named Risei, who is retired, emphatically not dead, and absolutely adores his son.
>   2. Kirei is a graduate of Le Cordon Bleu and was top of his class, despite (or possibly because of ) everyone being incredibly intimidated by him. 
>   3. At some point, he worked for one of Tohsaka Tokiomi's insanely expensive restaurants and was next in line to head one up before absconding with one of his top financiers and going off the grid for six months,
>   4. Tohsaka is still insanely furious about the last point.
> 


He goes to the stand after he gets off shift and Kirei's still there, eyes immediately focusing on him and refusing to be distracted.

“No, I'm not ordering,” Kiritsugu says. “I just want some answers.”

Kotomine shrugs. “You may ask.”

“Why on Earth would you run a small tofu stand in the middle of nowhere with your background? I know you have the money and the skill to open anywhere.”

“So you'd like one bowl of mapo tofu?”

“I asked you a question.” Kiritsugu grits his teeth.

“And I let you.”

He can see he's going to get nowhere just as he can see what Kotomine's going to yell after him when he leaves, so he decides to just get it over with and leave.

 

### Day Four

It's the start of a brand new Kiritsugu, one that has moved on from tofu stands that don't sell tofu staffed by people who don't answer questions. It's a Kiritsugu that's going to focus on work, try new food (not mapo tofu), and forget anything about vast culinary conspiracies involving famous Japanese chefs.

It's a Kiritsugu that's working the night shift with all the drunks in town and it's really trying his presence.

It's bad enough when he gets the regular ones, the kids that sob before keeling over in the streets, or the loud salarymen that insist they're fine before passing out cold. But tonight he's got a couple of special ones that are determined to drive him insane.

“Listen, my friend!” the big one yells as he claps a friendly hand on the blond one's shoulder. “I may disagree with your philosophy, but I respect you immensely!” He beams a drunken toothy smile.

The blond one snorts. “If I only I could save the same thing about the places you've taken me to. The alcohol there is weak and appalling. They should be ashamed of serving it.”

The big one is a bit crestfallen, then perks up. “Then what would you suggest?”

“I know a man who has an excellent wine collection,” his friend says. “And he rarely takes advantage of it, so we may feel free to do so.”

“Then to this friend's domicile we go!”

Kiritsugu feels like he should interrupt this, perhaps with a stern warning about public intoxication, but frankly, it's late, he's tired, and there's less than an hour to go before he's relieved by the next officer, so he just says, “Is there someone we can call for you?”

“I think he's referring to me,” Kiritsugu hears from behind him, and his first thought is oh no, for fuck's sake no, why is this happening to me, I had one day without him and now he's back, why does this universe hate me so much?

Out loud, however, he says,”I should have known, Kotomine, that you'd be involved in this.”

Kotomine comes into view, still wearing his dark blue jacket. “I'm sorry to cause you such inconvenience,” he says politely. “I hope my colleague hasn't been troubling you too much.”

The blond one laughs. “Is this the one, Kirei, that you've been--” Kotomine's hand shoots out and goes over the man's mouth.

“I apologize once more,” he says. “We shall be leaving now.” With that, he hauls the man up with one arm, and turns to the large man. “I'm afraid your drinking party is over for now.”

The blond man is still snickering, as Kotomine turns to look over at Kiritsugu. “I hope I shall see you again tomorrow. Perhaps for a bowl of mapo tofu?”

He resists the urge to throw his keys at him as the two leave.

The big gentleman, quiet through most of this, slaps a comforting hand on his back. “I wish you the best,” he says. “Truly, love is a hard road to walk down.”

Kiritsugu needs a drink.

 

### Day Five

It's not often that Kiritsugu runs into his former superior, especially since he's been actively avoiding her, but it's the way his life has been going that he sees her at the bakery as he's trying to figure out which pastry Illya would like the best.

“Emiya,” Artoria Pendragon says, her voice as calm and cool as ever. “It's been a while.”

“Yes,” he says. “I've been busy.”

“I've heard,” she says. “One of my... acquaintances ran into you last night.”

There's a sick feeling in his stomach but he moves past it. “I ran into a lot of people last night.”

“This one caused you a bit of trouble. I believe he and his friend had a bit too much to drink.” She smiles tightly. “He does that quite a bit.”

Process of elimination and the fact that he's a great detective means the blond one. “Well, he wasn't that bad.”

“Then he wasn't trying that hard.” She lays a hand on his arm. “I'm glad to see you're doing better.”

Kiritsugu swallows. “Is that what he said?”

Artoria's voice is gentle and firm as she continues, “I know it's been hard for you since the divorce, but it's good that you've found someone new. It's not a crime to want companionship and I think Iri understands.”

She's always been able to get people to confess just by talking to them, and he's not surprised that she knows what's going on in his life-- wait a minute. His brain catches up to what she's been saying. “Companionship? Iri understands?”

Artoria blushes. “Iri and I wanted to wait until you were in a more stable place to tell you, but Gil says that Kotomine's been a great help to you in dealing with your issues. We're both so glad to hear that you've started to try to change your habits.”

Kiritsugu doesn't know what to say. There is a distinct possibility he has gone insane.

She smiles at him. “We'll see you at dinner tonight.”

He's still trying to get past the whole implications about Kotomine when she adds, “Sometime in the future, you could invite him as well. I hear he's a great cook. Especially with tofu.”

Artoria walks out the door and Kiritsugu really wants to scream very loudly.

 

### Day Six

The next day Kiritsugu calls out. Maiya's concerned since he's never taken a sick day in his life, but he manages to reassure her that no, he isn't dying or injured or being held hostage by vicious criminals and she needs to rescue him singlehandedly. He just needs to be left alone for a day and it's miserable out enough that he doesn't feel any need to go outside.

Kiritsugu stares listlessly at the ceiling. He probably should be taking inventory of his life – working with his ex-girlfriend at his job, having dinner with his ex-wife and his ex-boss once a week, and being stalked by a mad tofu chef who seems bound and determined to cook for him. He quit smoking a month ago after the divorce but he's this close to finding the stale pack of cigarettes hidden in his closet and chain-smoking them.

At some point, he falls asleep to the sound of rain coming down and dreams of snowy landscapes where he's always trying to run after people who slip out of his hands. It changes to flames all of a sudden, a city falling in ruins around him and there is a booming in the sky that wakes him.

First, he thinks it's thunder before his bleary mind catches up and he realizes it's a solid knocking at the door. He stumbles to his feet.

“Maiya, I promise you there are no terrorists in my house,” Kiritsugu says as he swings the door open.

He will swear later he did not scream, but he does admit to himself, there might have been a stifled shriek at seeing Kotomine there, holding a large bag and staring at him.

“She said you were sick,” he says, making his way past him into the apartment. “I'm here to look after you.”

“Maiya told you I was sick,” Kiritsugu says, trying to kick him as he passes. “I really doubt she volunteered that information.”

“Hisau did threaten to pepper spray me, but I told her it would be highly ineffective on me.”

Kiritsugu laughs despite himself. “I'd imagine after mapo, it would be like a cool breeze to you.”

Kotomine's smirk widens. “That is the advantage of my cooking.”

“I'm not eating it, though.”

“Of course not,” he says, pulling out several containers. “It needs to be made fresh.”

Kiritsugu puts a hand on his wrist, stopping him from opening one up. “Be honest for once. Why are you so obsessed with getting me to eat your cooking?”

“Because you're the only who can truly understand me.” Kirei's hand grabs his own, grabbing it with a surprising strength. "I want to you to know every part of me."

What do you say to that?, Kiritsugu thinks. No, because I know there's something empty and dark in me that responds to who you really are. Your friend Gil is quite possibly the biggest asshole I've ever met in my life, with the exception of you. You've taken away all my hiding spots, everything that makes me feel steady, and replaced it with something that gives me no peace. We both know this is almost certain to end horribly but you're looking forward to it and I'm not going to try to stop it. 

“What the hell,” he says. “I'll give it a shot.”

Kirei leans over and kisses him and his mouth tastes of spice.

 

### Day Seven

Kiritsugu wakes up the next morning to his eyes burning and the smell of peppers coming from his tiny kitchen. Kirei's at the stove in a pristine white apron, chopping something on a board. There's a wok with oil frying on the stove.

“You don't give up, do you?” Kiritsugu says as he wanders over to peer over Kirei's shoulder.

“I think you'll find,” Kirei says as he turns to smile at him, terrifying Kiritsugu just a little bit, “that once I take an interest in something, I never lose it.”


	2. Chapter 2

**Summary for the Chapter:**

> Kotomine's (terrifying) perspective on courtship.

### Day Seven

He'll have to tell Gil that he's an idiot, Kirei idly thinks, as he sucks at Kiritsugu's neck. Calling someone like Kiritsugu boring – a man who refuses to admit he's having pleasure, fights it as long as he can stand, until he cries out and tries to stifle his voice, ashamed of the noises he's making. The beauty in such a man is getting past the flat surface, digging into him so deeply that you are inextricably bound together. It's not a love anyone normal would understand. That's what makes it so special. 

“I hate you so much,” Kiritsugu says, as he arches back, his hands twisting in the sheets. “You are the worst person in the world.”

Kirei smiles sweetly back at him. “I feel the same way.” He nips at Kiritsugu's lips until he draws blood. 

 

### Day Six

Kiritsugu doesn't show up at the stand, which is completely unacceptable. He knows the man's scheduled for duty and he's been waiting for him all morning, in between fending off potential customers, all of whom deserve to be denied his food. To send them away hungry and depressed that he considers them to be unworthy of eating his food and thereby ruin their day is a true delight. 

So it doesn't bother him to flip the sign on his stand to closed, tell one of his nameless employees to make sure no one steals anything, and walk away, leaving a trail of disappointed people in his wake. After all, there's something much more important than running a business at stake here. 

Kiritsugu's not at the kōban, but that partner of his is, which is annoying. 

“I'm here to see Emiya,” he says. “Where is he?”

Hisau peers at him suspiciously. “I don't see why it's any of your business,” she says. Her hand's reaching under the desk for something.

It would be an interesting turn for the day if she pulled her weapon on him, Kirei thinks, but he doesn't hold out much hope for it. “Is he unwell? He doesn't strike me as the type of man to casually take a day off.”

“And you know him so well.”

“I do,” he says. “Intimately.”

She really wants to shoot him, he thinks, judging from the look on her face. “Then I don't need to confirm anything, do I?”

He bows his head slightly. “Well, I'll take my leave. Goodbye, Officer Hisau.” 

“I could stop you,” she says. Hisau raises her hand from under her desk to put a canister of pepper spray on top. 

“I wasn't aware those were standard issue,” he says mildly. 

“They're not,” Hisau replies. “But somehow, I don't see you filing a complaint about it.”

Kirei smiles. “Well, I wouldn't want Kiritsugu to lose his most valued subordinate. Who knows what that might do to him?”

 

### Day Five

Gil's lounging on his couch in the morning, which isn't a surprise. Nor are the empty wine bottles strewn about him, as Kirei neatly steps over one that rattles around the floor. “How long are you actually staying this time?”

“Why?” he asks. “Are you afraid I'll scare away your boyfriend?”

Kirei sets the wine bottle on the table. “He's not my boyfriend. Not yet.”

“Of course not.” Gil snorts. “You take patience to a whole new level. Honestly, just take what you want. That way, you'll find out he's boring and not worth it and we can move past this little obsession of yours.”

Naturally Gil doesn't understand. He's never had to work for what he wants, let alone have to figure out what that might be. He's a simple creature, which made him so easy to sway. Just keep him entertained, never let him keep the upper hand, and make sure you have alcohol on hand at all times. It's like having an exceptionally irritating, inebriated cat. 

“Unlike you,” Kirei says. “I prefer to plan things out. We can't all rush into our conquests assuming they'll just succumb to our massive charm. Speaking of which, how is Artoria these days? Still avoiding you entirely, I assume?”

Gil throws a pillow at him, which Kirei dodges. “That was low and surprisingly hurtful of you. I'm very proud,” he says. “Perhaps you're not so hopeless after all.” 

“I do my best,” he says. “I'm sure if you stick around, I can think of a few more ways to cause you pain.”

Gil waves his hand lazily at Kirei. “Relax, I don't plan to be here very long. In fact, this magnificent idea has just occurred to me.” He pulls out his phone from his pocket. 

“I'm almost terrified to ask. Is it an idea that involves you leaving soon?”

There is no expression Kirei hates more than the one that crosses Gil's face. It's a smug, knowing, plotting one and it means that whatever happens next, Gil will be deeply pleased with himself about it.  
“Oh, just as soon as I get in touch with a friend.”

 

### Day Four

It's a mixed blessing, Kirei thinks, as he walks to the kōban. On the one hand, he gets the opportunity to meet Kiritsugu, needle him a bit, and see if he can get him to snap again.

On the other hand, he has to deal with Gil. A drunken Gil, at that, though really, there are only three states that Gil is usually in – drinking, drunk, and recovering from drinking before getting drunk again. It's a good thing he kept one of Gil's cards from his last bender, because his wine cellar is still recovering from the thorough pillaging it received. 

It's' not surprising that when he arrives there, Gil's leaning against some large man and bitching about low quality alcohol. Kirei resigns himself to the fact that his house will be completely cleaned out by the morning. He'll be lucky if he even has mouthwash left. 

Kiritsugu sounds tired and annoyed which is perfect, as he says, “Is there someone we can call for you?”

Bless him for giving him the perfect opening. “I think he's referring to me.”

The look of sheer “fuck my life” on Kiritsugu's face is breathtaking. It would be delightful if Kiritsugu just snapped and tried to strangle him, but all the man says is ”I should have known, Kotomine, that you'd be involved in this.” 

He decides to be nice tonight. It'll be so much more aggravating. “I'm sorry to cause you such inconvenience. I hope my colleague hasn't been troubling you too much.”

Sadly, Gil isn't drunk enough that he doesn't figure this one out immediately. “Is this the one, Kirei, that you've been--” 

With a reflex honed from far too much experience, he slaps a hand over Gil's lips. “I apologize once more,” he says. “We shall be leaving now.” He grabs Gil with his arm, and hefts him upwards, turning to whatever stranger Gil picked off the street. “I'm afraid your drinking party is over for now.”

Gil's laughing still, but he's not saying anything, so Kirei considers it a victory. And just to make it complete, he looks at Kiritsugu and says, “I hope I shall see you again tomorrow. Perhaps for a bowl of mapo tofu?”

The overwhelming rage on Kiritsugu's face keeps him warm all the way home. 

 

### Day Three

“Kirei?”

“Father? Is everything all right? I just talked to you yesterday?”

“No, everything's fine with me. However, I have a rather odd question for you?”

“Yes?”

“Is there a reason that Sergeant Emiya might be calling me to ask if I'm dead?”

Silence.

“Kirei?”

“I'm still here, father.”

“I know that's a surprising thing to say, but he called one of my former colleagues looking for me. He seemed to be under the impression that I was dead.”

“I don't know why he would think that. I told him I was taking over from you.”

“It seems like he didn't believe you. How strange.”

“Yes, father, it is.”

“Well, I talked to him and told him what a wonderful son you are.”

“Father--”

“How much you care for others, how you were willing to give up your restaurant just to help with the family business, how you've always been a pious and good soul.”

Silence again.

“Kirei?”

“Sorry, father. I just had something to clear from my throat. I'm grateful and touched by your kind words. 

“Well, I love you, son, and I hope that I've cleared up any misconceptions the sergeant might have.”

“I'm sure you have, father. I love you, too. I'll talk to you again tomorrow.”

Kirei hangs up the phone. He can see Kiritsugu approaching. 

 

### Day Two

Kiritsugu runs away again, and Kirei swears the man's getting faster at avoiding people, even though it's considerably more crowded at the stand than the day before. 

He had never planned to take over his father's stand. Not really. He had a fairly comfortable life at Tohsaka's. Sure, the daughter despised him (which was amusing for a time), Tohsaka was completely conventional when it came to cooking, and the rest of the staff were predictable at best, but it wasn't an unhappy life. It just was. 

Gil showing up wasn't even that exciting at first. Another financier Tohsaka was trying to court into financing an expansion for his business and this one was a pain in Kirei's ass. Always invading the kitchen, making snide comments, and most seriously, showing up in Kirei's house without being invited. He changed the locks three times and yet somehow, he'd always come home to find the man drinking wine on his couch. 

“You know,” Gil said to him one day, “you should really get married again. Make your life as miserable as possible. Maybe you can invite your daughter to the wedding and you can have the privilege of her turning you down.”

If it was meant to hurt, it really didn't. Kirei felt nothing, though he supposed he should. 

Another day, Gil says to him, “Or you could date that guy that's always stalking Tokiomi and his wife. He's messed-up enough for you. I'm sure you'd have a great time trying to fix him.”

He doesn't respond to that either. He's never letting Gil know their history. 

Kirei just drifts through his days in a bored haze, letting Gil crash at his place while he works for a man who constantly praises him even as he takes credit for all the work he does. 

Then one day, his father calls and asks him to stop by his stand. He has to talk to him. 

Kirei shows up at the stand and watches him for a while. His father's always been old but somehow the man seems ancient now. He's still strong though, hefting bags of potatoes like they weigh nothing. 

The stand doesn't get very many people, though, and he wonders if his father's going to tell him that he's closing the stand down. It'd make sense. No use in keeping a dead thing alive. 

And then he sees a man approach the stand. He doesn't look at anyone, doesn't talk to his father, just orders a burger and his father nods. The man gets his food, turns around, and Kirei gets a look at his face.

That night, he comes home and kicks Gil in the shin, waking him up on the couch. “I want to take over my father's stand and I want you to help me out.”

Gil's eyes gleam at him. “Finally, you've said something interesting.”

 

### Day One

There's a man in a police uniform standing in front of Kirei. He's dark haired, has a grim expression on his face, and his fingers are twitching. He's glaring at Kirei, which sets off his eyes nicely. 

“Where's the owner?” the man asks. He's definitely impolite about it. 

“My father's not here,” Kirei says. “I'm his son, Kotomine Kirei.” He keeps looking in the man's eyes, seeing him grow uncomfortable as he refuses to look away. 

“Well, I'm a regular and I'd like to order--”

“One bowl of mapo tofu,” Kirei's happy to see the man get even angrier. 

“Excuse me?” he asks. 

“You'd like to order that.”

“No!” the man snaps. “I used to--”

“That's all I sell,” Kirei says. He moves until he's right next in front of the man, seeing his body tighten up at the closeness. ”So that's what you're getting.” 

The man storms away. Kirei keeps a particular eye on the man's ass. It's lovely. 

Just for fun, he calls out, “You'll be back.”

Once the man's in the distance, he smiles and says, “It's a pleasure to meet you, Kiritsugu.”


End file.
